Electrochemical kinetic parameters of a metal hydride battery electrode

The electrochemical properties of the LaNi 3.55 Mn 0.4 Al 0.3 Co 0.4 Fe 0.35 electrode were investigated using the micropolarization measurements. The exchange current density, the polarization resistance, and the equilibrium potential were determined as a function of the state of charge (SOC) in the electrode. The micropolarization measurements indicated that the electrochemical kinetic property was improved with increasing SOC, due to the increase of the electrocatalytic activation of the surface and the increase of the hydrogen diffusivity in the alloy bulk.